Evolutionary diversification via modular compliance for self-reconfigurable continuum robots.

Modular self-reconfigurable robots promise adaptability through changes in morphology, yet most existing systems remain limited by low functional density, rigid modules, and constrained docking interfaces that restrict scalable locomotion and manipulation. In contrast, biological organisms achieve rich behavioral diversity through repeated compliant segments combined with flexible articulated body architectures to support locomotion, manipulation, and environmental interaction. Here, we present a modular self-reconfigurable continuum robot that exploits modular compliance as a unifying design principle to enable cross-species bioinspired loco-manipulation within a single platform. Each module integrates a continuum backbone for compliant bending and a pair of grippers for omnidirectional, quasi-freeform docking, achieving high functional density within a compact unit. As a result, a small number of modules can assemble into diverse morphologies capable of distinct capabilities. We further develop a morphology-conditioned gait library covering rolling, undulation, crawling, quadrupedal walking, and multisegment manipulation, organized within an evolutionary diversification tree that explicitly links biological locomotion strategies to corresponding robotic assembly patterns. To enable autonomous transitions between configurations, we introduce a unified geometric-topological representation and a self-reconfiguration planner that decomposes reconfiguration into discrete grasping and releasing actions and continuous deformation actions. Hardware experiments demonstrate online self-reconfiguration, followed by integrated loco-manipulation. Together, these results show that embedding compliance at the module level unifies locomotion, manipulation, and self-reconfiguration within a single robotic platform, suggesting a pathway toward more adaptable machines that exhibit organism-like behaviors across species.